Motion-picture film developer feeding device



Dec- 25, 1951 H. w. HOUSTON 2,579,741

MOTIONwPICTURE FLM DEVELOPER FEEDING DEVICE Filed Nov. 18, 1946 3Sheets-Sheet l ATTORNEYS N m R U O 0 aww mw N M I H N E w. W TIMJ ,I-All/..-Iqhj l l l l .l x), n F1, y x l L H mm B m H `Nlll..\||.|||l|||| l. -I IJ n t n. m wllrwlllmr.. .U 1.4m Im H IH mw @vI|IIIIIIII|NIIF|M|I nu L M., lnf. mi wm l@ M ,vm i M omN v M MN mh mDec. 25, 1951 H. w. HOUSTON MOTION-PICTURE` FILM DEVELOPER FEEDINGDEVICE Filed Nov. 18, 1946 3 Sheets-Sheet 2 N w s Y m n T. Un m m .m w MM .I R E B M m m 3N E. f

mm s?. IlNm f amm m SN FIG 3 Dec. 25, 1951 H. w. HOUSTON `2,579,741 lMoToN-PICTURE FILM DEVELOPER EEEDING DEVICE Filed Nov. 18, 194e 3Sheets-Sheet 3 INVENTOR HERBERT w. Housou ATTORNEYS Patented Dec. 25,1951 i MOTION-PICTURE FILM DEVELOPER FEEDIN G DEVICE Herbert W. Houston,Sherman Oaks, Calif., assignor, by mesne assignments, to Houston-Fearless Corporation, Los Angeles, Calif., a corporation of CaliforniaApplication November 18, 1946, Serial No. 710,558

4 Claims.

color film requires exposure to certain light rays during thedevelopment process, which is generally referred to as flashing theiilm.

As the iilm, which is placed in the machine as a dry undeveloped roll,progresses through the developing process, the wetting of the iiim tendsto elongate it. This elongation may amount to approximately two percent(2%), while in the drying of the film it may shrink to even less thanits original length. The final finished length of the lm may beapproximately ninety-eight percent (98%) of its original dry length.

In order to insure proper feeding of the film at all stages of thedeveloping process, it is desirable to maintain the nlm under light butconstant tension during its progress through the developing machine andalso to keep the traveling loops of the iilm immersed to a constantdepth in the various baths through which the film is passed. Variousexpedients have been resorted to in an attempt to take up the slackproduced by this elongation of the film, at its intermediate stage ofprogress through the developer, but up t0 the present time nosatisfactory development for this purpose has been achieved so far as Iam aware. The result has been that at times valuable original filmswhich were irreplaceable have been damaged by the presence ofuncompensated slack in the film during its progress through a developingmachine.

An object of the present invention is to make an improved and simpliediilm feeding mechanism for a developing machine.

Another object is to make a film developing machine for continuouslyprocessing motion picture film with means for maintaining a positivedriving action on the film through its length and to compensate forelongation and shrinkage of the film during its progress through thevarious stages of the machine.

Another object is to make a film feeding device for a motion picture nlmdeveloping machine wherein substantially uniform tension will bemaintained on the lm throughout its driven length, and whereinelongation of the iilm will produce an increased length of film looptogether with an accelerated driving speed at an intermediate stage ofthe iilms travel through the machine.

Another object is to maintain uniform tension with variable speed drivedriving characteristics on a motion picture film as it progressesthrough a developing machine.

These and other objects of the invention will be more fully set forth inthe following description and the accompanying drawings, comprisingthree sheets. In the drawings:

Fig. 1 is a side elevational View of a motion picture film developingmachine embodying the present invention, an upper closure plate alongone side of a developing compartment being removed to show the interiorof the compartment; film driving mechanism, solution tanks, :and lowernlm guiding rollers being indicated in dotted lines;

Fig. 2 is a view, partly in plan, and partly in horizontal section,taken on the offset line 2 2 of Fig. 1;

Fig. 3 is an enlarged fragmentary vertical transverse sectional viewtaken on the line 3-3 of Fig. l;

Fig. 4 is a similarly enlarged fragmentary horizontal transversesectional view taken on line 4-4 of Fig. 3; and

Fig. 5 is a similarly enlarged fragmentary vertical longitudinalsectional view taken on the line 5--5 of Fig. 4.

Referring to the drawings in detail, a film developing machine comprisesthree main compartments, namely, a iilm drying compartment l0, anintermediate motor drive compartment I I, and a iilm developingcompartment I2. The developing compartment I2 has a plurality ofsolution tanks I3 therein, and is completely enclosed by removableclosure plates I4 which are joined to each other and to a framework I5of the compartment so as to provide a light-tight enclosure.

A film chamber I1 is provided in the intermediate compartment II inwhich a frictionally retarded reel I8 of exposed but undeveloped motionpicture film is pivotally mounted. A pair of idler rollers I9 and 20 arepivotally mounted in the chamber Il, in line with the supply reel I8,the idlers being positioned adjacent a slotted openng 2l in a wall 22which separates the central compartment II from `the developingcompartment I2.

A plurality of film guide and drive pulley assemblies 23 are mounted inlongitudinal alignment along one side of the center of the developingcompartment I2, and a second pularity of such assemblies are mountedsimilarly along the other side of the center of the developingcompartment. Each of the main film drive assemblies 23, as illustratedparticularly in Figs. 3, 4 and 5, comprises ve drive pulleys 24pivotally mounted on a common driven shaft 25. n

The periphery of each of these pulleys has side fianges 21, betweenwhich to receive a film 29 of a width for which the machine is designed.The central portion of the base of the peripheral face of each pulley 24is recessed slightly as at 28 to i avoid contact with the centralportion of the film 29 being processed. A cross sectional View of the lmas it appears supported on the pulleys is illustrated in Fig. 3.

Each of the lm drive pulleys 24 has a relait'.

tively large hub portion 39 with an annular endwise recess 3! around acentral shaft opening 32 therein, in which is journaled the driven shaft25. Interposed between adjacent pulleys 24 are a plurality of annularfrictional drive members 33 .1,-

having clutch faces 34, of suitable frictional material such as asbestosclutch facing material, secured to opposite sides thereof. A drive key35 is mounted in each of the annular frictional members to extend intothe central opening i thereof.

The driven shaft has a longitudinal keyway 31 therein adapted slidablyto receive the inwardly projecting ends of the keys so as to provide apositive drive for these annular frictional members from the shaft 25and at the same time permit slidable movement of these members axiallyof the shaft.

An annular frictional end drive member 38 is provided on the inner endpulley of each group 23, and this end member has a frictional facing 34on one side only thereof. The other side of the inner frictional drivemember abuts against a collar 35 which is fixed in position on the shaft25 by a pin 40. Another annular frictional end drive member 4i isslidably mounted on the shaft 25 at the outer end of the grouo ofpulleys. rihis outer end member also has a frictional facing 34 securedto one side only thereof. The outer side of this outer end member 4I isengaged by a compression coil spring 42, the outer end of which engagesa collar 43 secured in adjusted position adjacent the outer end of theshaft 25. This arrangement of the frictional drive members and thepulleys 24 provides an adjustable clutch type of driving arrangement foreach of the pulleys. but allows some individual slippage of the pulleysto compensate for minor differences in the lengths of the lm loopspassing over the film drive pulleys 24.

The driven shaft 25 is reduced in diameter4 gitudinal inner wall 53 ofthe developing cornpartment l2. A coil spring 54 is connected in tensionbetween the hub 48 and an adjusting screw 55 which is supported by aknurled nut 5'.' from the top of the compartment. rIhis tends to drawthe hub 48 upwardly about the pin 5l as a pivot to the'upper limit ofits movement.

The wall 53 has an arcuate slotted opening therein which permits limitedarcuate up and down movement of the hub 48 about the pivot pin 5i as acenter.

A divided V pulley 58 is mounted on the driven shaft 25 on the oppositeside of the wall 53 from the pulleys 24. One portion 59 of this dividedpulley is affixed to the shaft 25 by a pin 58. The other portion 5I ofthe pulley is slidably mounted on the shaft 25 and on drive pins 62mounted in the fixed pulley portion 59. The slidable portion 6I of thepulley is urged toward the fixed portion 59 by aV coil compressionspring 83 which bears against the outer side of the slidable pulleyportion 5I, the other end of the spring being engaged by a knurledadjusting nut 54 threaded onto the end of the shaft.

A V belt passes over the divided pulley 58 and is driven by a V drivepulley 81 which is pivotally mounted on a stub shaft 68 secured in abracket 59 mounted on the wall 53. The V drive pulley 61 has an extendedhub portion 18 with a driving sprocket 1| secured on an end thereof. Thecombination V pulley and sprocket is retained on the stub shaft 68 by Vasuitable retaining washer 12.

A pair of drive chains 'I3 and 13a (see Figs. 1 and 2) are mountedlongitudinally of the developing compartment on opposite sides of thecentral partitions thereof to have driving engagement with the sprockets1I. Idler sprockets i4 are provided between each second pair of filmdrive pulley assemblies to retain the drive chains in driving engagementwith the sprockets. y

The drive chains 'F3 and 13a are driven in opposite directions fromeachother by a motor l5 which is provided with suitable speed reducerand control mechanism 11 of a usual type which drives a bevel drive gear18. The bevel drive gear is in driving connection with a pair' of drivenbevel gears 19 and 80 which are mounted coaxially with each other, butare pivoted relatively to each other so as to permit them to ro.- tatein opposite directions under the driving impulses of the bevel drivegear 18.

The driven bevel gear 19 has driving ceniiection with a short shaft 80,which is connected by' sprockets and a drive chain 82 to a countershaft83. The countershaft has a sprocket secured thereto which has drivingengagement with one main drivev chain 13. Similar driving engagement isprovided fromthe beveled drive gear 18 to the other main drive chain13d.

A plurality of nlm loop lower end idler pulleys 85 having peripheriesgenerally similar' to but -of smaller diameter than the pulleys 24' aremounted, in groups corresponding to their respective drive pulley groups23. The idler pulleysv sufficiently through the bushings as shown inFigure l to enable the operator to manuallyZV grasp the end caps ontheir upper ends for raising therrods and idler pulleys mounted thereon.

A cross-over arrangement for carrying the film from one side of themachine to the other is provided by the arrangement illustrated at theleft end of Figs. 1 and 2, In this arrangement but three lm drivepulleys 24 are mounted on a driven shaft assembly 23a. A cross overidler pulley 9i is mounted with its axis at right yangles to the pulleys23a in position to receive the film as it passes up from the outer loweridler pulley 85. The 'film is twisted through an angle of 90 as itpasses from the lower idler pulley to the crossover idler pulley 9|. Thefilm crosses over to the other side of the developing compartmentthrough slotted openings B2 and 23 in the innerl walls of the developingcompartment, and passes over a second idler pulley 94 mounted in linewith the first idler pulley 9i. From the second idler pulley 94 the filmpasses downwardly through a quarter twist to the inner lower idlerpulley 85 of a group 23h of feed pulleys. Thence it passes around aseries of groups 23 of feed pulleys along the other side of thedeveloping compartment toward the drying compartment Ill.

From the last group 23 of film feed pulleys in the developingcompartment the film is directed through suitable slotted. openings intothe drier cabinet Ill. Here the film is run over a series of feedpulleys 23o indicated in dotted lines in Fig. l, which are similar tothose used in the developing compartment and similarly, automatically,adjustably mounted, and around a series of freely rotatable lowerpulleys 851) which are similar to those carried by the slide rods 89 inthe developing compartment.

The drying cabinet is higher than the developing compartment so as toaccommodate greater film length in a smaller floor space. The dryingcompartment is provided with suitable heat and humidity controls, andair circulating and filtering means so as to maintain a required flow ofclean air having proper temperature and humidity for drying the film.

After the lm has completed its run through the drying compartment, it isfed outwardly under an idler pulley 95, through a slotted opening in theside of the drying cabinet, over a frictionally driven pulley 5l', andonto a frictionally driven takeoff reel 98.

In using the device, suitable developing, washing and fixing solutionsare introduced into the various tanks before beginning the developingprocess. In order to carry the film through the various stages of themachine, a leader, which usually is a length of special leader materialof the size for which the machine is designed, is rst threaded throughthe machine and around the pulleys in the same course which the film tobe developed is to follow. During this initial threading process theslide rods 89 are pulled upwardly to their full limit of movement so asto bring the lower idler pulleys 85 closely beneath the film drivingspools 24. In case one of the tanks is not to be used in the developingof a particular lm, the film is bypassed directly across this tank, asillustrated at 29a in Fig. 2.

After the leader has been threaded through the machine, the film feedingmechanism is started up slowly by energizing the driving motor 'i5 withthe speed control mechanism 'il properly retarded. The slide rods 8Sthen are moved downwardly to their full limit of movement to elongatethe loops of film and to carry them well down into the tanks ofsolutions. As the lower idler pulleys are secured to the lower ends ofthe slide rods 89, the pulleys 85 will, when the rods 89 are in theirlowermost position, also occupy their lowermost positions during normaloperative conditions of the developing machine and will not be loweredor raised by any lengthening ori shortening o1' 'the film, due 'towetting or drying thereof. The Weight of the pulleys 85, shafts 8l' androds B9 will hold the pulleys ver, tically stationary in their lowermostposition under normal operative conditions, any relatively small changein length and tension of the lm loops being reected in vertical movementof the upper pulley shafts 25 which are held floatingly in position bythe coiled springs I54. After the leader has thus been threaded andextended, the end of the exposed but undeveloped film is spliced to theend of the leader, and the film feed rate is speeded up, as by means ofthe variable speed control mechanism 11 to a required developing speed.This speed may be in the neighborhood of one hundred feet per minute,although the speed of developing may vary greatly with the size and typeof film to be de-V veloped and the types and strengths of solutionsemployed.

After the leader has completed its run through the machine, itordinarily is cut off from the actual film being developed which then isthreaded onto a new take-off reel 98 which replaces the one which hasbeen used to receive the leader.

As the dry undeveloped nlm enters the machine at a predetermined speed,the driving force imparted to the film by the feed pulleys 24 throughthe V belt 65 and the divided driven pulley 58 has a tendency to holdthe feed pulleys 24 downwardly against the tension of the coil springs54. This action decreases the center to center distance of the dividedpulleys 58 and the V drive pulleys 6l. The compression coil spring 63forces the sliding pulley portion 6| toward the fixed portion 59, andthereby forces the V belt radially outwardly. This increases theeffective diameter` of the driven divided pulley 58.

As the film progresses through the solutions in the tanks of thedeveloping compartment and becomes thoroughly wet, it elongates, andthis elongation of the lm eases the tension on the film and permits thecoil tension springs 54 to raise the hubs 48 upwardly about their pvotpins 5I.

As the springs 54 movethe hubs 48 upwardly, the center to centerdistance of the pulleys 58 and 6l is increased. This forces the V drivebelt 65 radially inwardly on the divided pulley 5B, theref by forcingthe slidable portion 6| of the divided pulley axially outwardly againstthe force of the coil compression spring 63. This reduces the effectivediameter of the divided driven pulley 58, which increases the speed ofrotation of the driven shaft 25, and thereby increases the rate of feedof the iilm 29.

After the film has passed through the developing phase and enters thedrying compartment IU and is dried, it again shrinks gradually back to alength approximating its original length. This increases the tension onthe film, which again tends to draw the pulley assemblies 23odownwardly, thereby elongating the tension springs 54 and, as set forthabove, positions the V belt at a proper peripheral distance on each setof pulleys to accomplish the proper driving effect required by the thusreduced film length.

Any irregularities in driving tension between adjacent pulleys within agroup are readily absorbed by slippage of the pulleys with respect totheir frictional driving members 33.

The device comprises a simple and positive film driving arrangementwhich maintains a substantially uniform tension on the film throughoutits length in the developing machine, and provides for driving the wetintermediate portions of the film in an elongated condition at thenecessarily more rapid rate than both of the relatively shorter dry endportions.

While I have illustrated and described a preferred embodiment of myinvention, it will be apparent to those familiar with the art that thedevice is capable of several changes without departing from the spiritof the invention. It is desired, therefore, not to limit the inventionexcept as speciiicially set forth in the following claims.

I claim:

l.v In a motion picture film developer, a lm feeding device comprising aplurality of lm drive pulleys rotatably mounted on a driven shaft, saidshaft being movable in a direction normal to its axis, frictional drivemeans having driven connection with said shaft and having frictionaldriving engagement with each of said pulleys, spring pressed meansmounted to maintain said pulleys in frictional engagement with saidfrictional drive means, a divided V belt pulley having aV portionthereof secured to said driven shaft, a second portion of said pulleyhaving slidable engagement with said driven shaft, and a power driven Vbelt having driving engagement with said divided pulley, said pulleybeing positioned to increase the driven radius of said divided pulley ona predetermined movement of said driven shaft in a direction normal toits axis.

2. In a motion picture film developer, a film feeding device comprisinga driven shaft mounted for bodily movement in a plane normal to theshaft axis, a plurality of film drive pulleys rotatably mounted on thedriven shaft, a plurality of frictional drive elements mounted betweenadjacent pulleys and having driven connection with said shaft, rstspring means mounted to press said pulleys into frictional drivenengagement with said frictional drive discs, a divided V belt pulleyhaving a first portion thereof secured to said driven shaft, a secondportion of said pulley mounted slidably on said driven shaft, secondspring meansmounted to press the second portion of the divided pulleytoward the first portion thereof, and a power driven V belt havingdriving engagement with said divided pulley, said pulley beingpositioned to increase the driven radius of said divided pulley one apredetermined movement of said driven shaft bodily in a plane normal tothe shaft axis.

3. In a motion picture lm developer, a lm feeding device comprising adriven shaft mounted for bodily movement in a plane normal to the shaftaxis, a plurality of film drive pulleys rotatably mounted on the drivenshaft, a plurality of frictional drive elements mounted between adjacentpulleys and having driven connection with said shaft, first spring meansmounted to press said pulleys into frictional driven engagement withsaid frictional drive discs, an adjustable control mounted to regulatethe pressure pressing said spring means into frictional drivenengagement with said discs, a divided V belt pulley having a iirstportion thereof secured to said driven shaft, a second portion of saidpulley mounted slidably on said driven shaft, second spring meansmounted to press the second portion of the divided pulley toward thefirst portion thereof, and a power driven V belt having drivingengagement with said divided pulley, said pulley being positioned toincrease the driven radius of said divided pulley on a predeterminedmovement of said driven shaft bodily in a plane normal to the shaftaxis.

4 In a motion picture film developing machine,

a plurality of film feeding devices, each comprising a first pulleymeans mounted for free rotation and including a pulley shaft at avertically lower level and held at said level by the weight of saidpulley means against relatively small elevating forces, a second pulleymeans including a pulley shaft and mounted at a vertically upper levelin alignment with the rst pulley means for Acarrying in cooperation withthe iirst pulley means a looped length of film, a coiled spring forvertically movably supporting the shaft of said second pulley means onthe developing machine in yieldable opposition to the tension of thelooped film, a V-belt pulley on the shaft comprising two axiallyrelatively movable disks, a spring for yieldably urging the disks towardeach other, a power driven V-belt pulley on the opposite side of thesaid shaft from said shaft supporting spring, and a V-belt for saidV-belt pulleys.

HERBERT W. HOUSTON.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,854,604 Steinmann Apr. 19, 19322,029,854 Cannity Feb. 4, 1936 2,079,849 Geib May 11, 1937 2,096,231Ensign et al Oct. 19, 1937 2,146,170 Brenbarger et al. Feb. 7, 19392,210,880 Capstaii Aug. 13, 1940 2,427,943 Butterworth et al. Sept. 23,1947

